

You can use USB token-resident IOS releases in two ways: You should see the USB flash devices: rommon 1 > dev Test the upgraded ROMMON with the dev command. You need ROMMON release 12.4(13r)T (description: C2800 ROMMON Upgrade adds boot from usb flash drive capability).Īfter you've downloaded the file onto a USB token, upgrade the router ROMMON with the upgrade rom-monitor file usbflash0:C2800NM_ command (requires router reboot). To support IOS boot from USB token, you need a newer version of 2800-series ROMMON which you'll get from the ROMMON download page (registered CCO users only). The product documentation states you can't, but as always, reality changes quicker than documentation in Ciscosphere.


As all 2800-series routers have USB slots, I started investigating whether you could boot the IOS image from an USB flash token. A while ago we were faced with a 2800-series router with no software in its CF card.
